This topic

DNS error when connected to work VPN via ethernet

RobP_Kent — Thu, 07 Apr 2022 16:03:45 GMT

Hope someone can assist as this is really bugging me.

I have Smart Hub 2 and am connected via ethernet network cable to hub

As standard this works perfectly and gives a rock solid connection for working from home

I have to use my workplace VPN to access an internal docs server and if I use the ethernet connection with any browser I get "This site cant be reached" with a message that the servers IP address cannot be found

If I type in the IP address of the webpage it works perfectly

If I disconnect the Cat6 cable and use WIFi it works fine too

Got a work colleague to test the same set up (he is on Virgin) and he has no issues so it appears there is a DNS issue when using Ethernet connection over VPN on BT hub (had the problem on my previous HH5 too)

Other than ditch the router and buy a non BT one does anyone have suggested solution please

Thanks Rob

Re: DNS error when connected to work VPN via ethernet

Keith_Beddoe — Thu, 07 Apr 2022 16:19:41 GMT

@RobP_Kent

Its possible that the VPN software is using the wrong DNS servers. If possible, try changing the DNS setting on the VPN so it uses Google Public DNS 8.8.8.8 and 8.8.4.4

If BT web protect is enabled, that that can cause issues, so try disabling it.

You cannot change the DNS settings on any of the BT home hubs.

Re: DNS error when connected to work VPN via ethernet

RobP_Kent — Thu, 07 Apr 2022 21:07:09 GMT

No DNS options on the VPN as just the standard built in windows VPN connected to company portal

Dont have web protect or smart setup enabled either

Re: DNS error when connected to work VPN via ethernet

TimCurtis — Fri, 08 Apr 2022 08:47:21 GMT

@RobP_Kent

Is it possible that you have manually set DNS in the device configuration for the ethernet and/or the wireless adapter that are different and causing the issue.

Re: DNS error when connected to work VPN via ethernet

Cliff — Fri, 08 Apr 2022 09:47:51 GMT

To start i'll say that i'm not a tech.savy guy.I had/have a problem getting into my bt email website,. ( Error code TS-0003)It appeared to have been sorted out but started up again & to get in i had to pause my VPN.After reading this thread i went into my vpn connection options & changed my protocol from the default Wiregaurd to the previous default open vpn & i had no issue getting into my bt em.

As i said i'm not tech savvy so have no idea if this might help with your problem,just thought i'd put it up anyway.

Re: DNS error when connected to work VPN via ethernet

RobP_Kent — Fri, 08 Apr 2022 10:16:43 GMT

@TimCurtis

No, I have not changed anything in device config at all (Everything is locked down with admin password!)

In fact I got a brand new laptop from work yesterday and we setup VPN connection from scratch and still the same as previous laptop.

My colleague who tested for me has no issues with an identical setup via Virgin and If I unplug the ethernet cable and use WIFI it works to!

Guess its just an issue with the BT router and the fixed DNS entries

Re: DNS error when connected to work VPN via ethernet

licquorice — Fri, 08 Apr 2022 10:27:20 GMT

When you say it works OK with WiFi, do you actually mean WiFi or do you mean 4G mobile data? If it works ok with hub WiFi but not with hub Ethernet, that would point to a problem with your laptop rather than the hub.

Re: DNS error when connected to work VPN via ethernet

licquorice — Fri, 08 Apr 2022 10:30:53 GMT

Try temporarily disabling IPv6 on your Ethernet adapter.

Re: DNS error when connected to work VPN via ethernet

mispeltyuoth — Fri, 08 Apr 2022 10:42:15 GMT

I had a similar issue when I tried using a work VPN. Our IT department said it does seem to be a problem with BT hubs and suggested turning on 'port clamping'.

Go into advanced settings on your hub and select VPN; turn on 'port clamping' and save the settings (I think that's how I did it)

Re: DNS error when connected to work VPN via ethernet

Keith_Beddoe — Fri, 08 Apr 2022 11:03:27 GMT

I would suggest that the company internal firewall program is only allowing DNS if you are at work, and plugged into the their Intranet.

Wireless connections would be treated as public connections, and there would be internal firewall isolation to prevent accidental linking of a public Wi-Fi connection, and the company internal LAN.

I seem to remember a similar issue with BT laptops when I used to work for them, in that you could only use the Ethernet connection while you were connected to BTs Intranet.

Re: DNS error when connected to work VPN via ethernet

licquorice — Fri, 08 Apr 2022 11:10:02 GMT

Except in the op's case, WiFi works but Ethernet doesn't.

Re: DNS error when connected to work VPN via ethernet

RobP_Kent — Fri, 08 Apr 2022 11:30:07 GMT

@licquorice

Yes I do mean actual WIFI from same router i.e. I unplug the ethernet cable and connect to the router via WIFI instead

Re: DNS error when connected to work VPN via ethernet

RobP_Kent — Fri, 08 Apr 2022 11:33:28 GMT

@Keith_Beddoe

No, as the DNS works fine when using VPN via WIFI and also works fine for my colleague with same set up connecting via ethernet or WIFI on his Virgin connection

Re: DNS error when connected to work VPN via ethernet

Keith_Beddoe — Fri, 08 Apr 2022 11:38:56 GMT

Except in the op's case, WiFi works but Ethernet doesn't.

That is what I would expect. Ethernet connections would be restricted to Intranet connections, and would use the company internal DNS settings which would be on their side of their firewall.

I would suspect that the Intranet public IP range, clashes with the home hubs reserved IP range for BT Wifi.

A different router would be the best option, provided Digital Voice is not provisioned.

Re: DNS error when connected to work VPN via ethernet

licquorice — Fri, 08 Apr 2022 11:36:34 GMT

????